6.6.3 : Manual vectorization (by Intrinsic functions)

• 6.6.3.1) Begining of the main_intrinsics.cpp file
• 6.6.3.2) The hadamard_product function
• 6.6.3.3) The function to evaluate performances
• 6.6.3.4) The main function
• 6.6.3.5) Full main_intrinsics.cpp file
• 6.6.3.6) The CMakeLists.txt file
• 6.6.3.7) Compilation
• 6.6.3.8) The performances with Intrinsics

The idea is to force the compiler to do what you want and how you want it.

The Intel intrinsics documentation : https://software.intel.com/en-us/node/523351

• Some changes (for AVX2) :
  • Include : immintrin.h
  • float : __m256 (= 8 float)}
  • Data loading : _mm256_load_ps
  • Data Storage : _mm256_store_ps
  • Multiply : _mm256_mul_ps

Only on aligned data of course.

Let's create a main_intrinsics.cpp file.